Study On Anti-UV Reactive Dyes

It is known that prolonged exposure to UV radiation is harmful to the skin. To protect thebody, clothing is a main barrier, but fabrics always have a high UV transmittance, soproducing textile products that afford protection against UV radiation continues to be aworthwhile undertaking. The objective of our work was to synthesize reactive dyes containinga UV absorber group, then cotton and silk were dyed with the target dyes to improve thetextile's anti-UV properties, and the application and anti-UV properties of the resultant dyeswere assessed.The starting materials 3-nitrobenzoyl chloride reacted with resorcinol or1,3-dimethoxybenzene, three benzophenone intermediates containing amino group weresynthesized by acylation, Friedel-Crafls, alkylation, reduction reaction: 2,4-dihydroxy-3'-aminobenzophenone, 2-hydroxy-4-methoxy-3'-aminobenzophenone, and 2-hydroxy-4-ethoxy -3'-aminobenzophenone. The optimal conditions of 2-hydroxy-4-methoxy-3'-nitrobenzophenone was obtained by orthogonal method. Benzoyl chloride reacted withresorcinol to give 2,4-dihydroxy benzophenone which did not contain amino group. Abenzotriazol intermediate was synthesized by diazotization, coupling and oxidation reaction as2-aminophenol-4-sulfonic acid and m-phenylene diamine: 2-(2-hydroxy-5-sulfophenyl)-5-amino-2H-benzotriazol. The structures of the intermediates were confirmed by MS,~1HNMR.As compounds used in diazotizing reaction were 4-(2-sulfatoethylsulfonyl)aniline or2-amino-5-(2-sulfatoethylsulfonyl)benzenesulfonic acid, twenty reactive dyes containing theUV absorber groups were synthesized by diazotizing, coupling and condensation reactions. Thestructures of the dyes were confirmed by IR, MS, UV—VIS.Cotton and silk were dyed with the prepared dyes, the application of dyes and the anti-UVproperties of dyed fabrics were tested. The UPF value of undyed fabric was 1.3, and the UPFvalues of fabrics dyed with orange, red and blue dyes were between 17-20 mostly, showinggood anti-UV properties. The UPF values of dyed fabrics after wash, rubbing and lightfastness tests were also measured. Compared with the dyes which had the same chromophoresand reactive groups but did not contain UV absorber groups, it can be found that the presenceof UV absorber groups influenced the ultraviolet absorbent properties of dyes indeed.